WIP: multi-connection advertising attempts (unsuccessful), iOS connection panel, app icon

cue-ios/CueIOS/AppState.swift

@@ -1,5 +1,6 @@
 import Foundation
 import Observation
+import Combine
 
 enum Tab: String, CaseIterable, Identifiable {
     case eis = "EIS"
@@ -8,6 +9,7 @@ enum Tab: String, CaseIterable, Identifiable {
     case chlorine = "Chlorine"
     case ph = "pH"
     case sessions = "Sessions"
+    case connection = "Connection"
 
     var id: String { rawValue }
 }
@@ -16,6 +18,7 @@ enum Tab: String, CaseIterable, Identifiable {
 
 @Observable
 final class AppState {
+    let ble: BLEManager
     var tab: Tab = .eis
     var status: String = "Disconnected"
     var bleConnected: Bool = false
@@ -74,52 +77,255 @@ final class AppState {
     // Device reference collection
     var collectingRefs: Bool = false
     var hasDeviceRefs: Bool = false
+    private var eisRefs: [Int: [EisPoint]] = [:]
+    private var refMode: UInt8?
+    private var refRtia: UInt8?
+
+    // Session
+    var currentSessionId: Int64? = nil
 
     // Clean
     var cleanV: String = "1200"
     var cleanDur: String = "30"
 
+    // Temperature polling
+    private var tempTimer: Timer?
+
+    init() {
+        ble = BLEManager()
+        ble.setMessageHandler { [weak self] msg in
+            self?.handleMessage(msg)
+        }
+        startTempPolling()
+    }
+
+    // MARK: - BLE connection tracking
+
+    func updateConnectionState() {
+        let connected = ble.state == .connected
+        if connected != bleConnected {
+            bleConnected = connected
+            status = ble.state.rawValue
+        }
+    }
+
+    // MARK: - Temperature polling
+
+    private func startTempPolling() {
+        tempTimer = Timer.scheduledTimer(withTimeInterval: 0.5, repeats: true) { [weak self] _ in
+            guard let self, self.bleConnected else { return }
+            self.send(buildSysexGetTemp())
+        }
+    }
+
+    // MARK: - Send helper
+
+    func send(_ sysex: [UInt8]) {
+        ble.sendCommand(sysex)
+    }
+
+    // MARK: - Message handler
+
+    private func handleMessage(_ msg: EisMessage) {
+        switch msg {
+
+        case .sweepStart(let numPoints, let freqStart, let freqStop):
+            if collectingRefs {
+                eisPoints.removeAll()
+                sweepTotal = numPoints
+            } else {
+                eisPoints.removeAll()
+                sweepTotal = numPoints
+                status = String(format: "Sweep: %d pts, %.0f--%.0f Hz", numPoints, freqStart, freqStop)
+            }
+
+        case .dataPoint(_, let point):
+            eisPoints.append(point)
+            if !collectingRefs {
+                status = "Receiving: \(eisPoints.count)/\(sweepTotal)"
+            }
+
+        case .sweepEnd:
+            if collectingRefs {
+                if let r = refRtia, r < 8 {
+                    eisRefs[Int(r)] = eisPoints
+                }
+                eisPoints.removeAll()
+            } else {
+                saveEis()
+                status = "Sweep complete: \(eisPoints.count) points"
+            }
+
+        case .config(let cfg):
+            freqStart = String(format: "%.0f", cfg.freqStart)
+            freqStop = String(format: "%.0f", cfg.freqStop)
+            ppd = "\(cfg.ppd)"
+            rtia = cfg.rtia
+            rcal = cfg.rcal
+            electrode = cfg.electrode
+            status = "Config received"
+
+        case .lsvStart(let numPoints, let vStart, let vStop):
+            lsvPoints.removeAll()
+            lsvTotal = numPoints
+            status = String(format: "LSV: %d pts, %.0f--%.0f mV", numPoints, vStart, vStop)
+
+        case .lsvPoint(_, let point):
+            lsvPoints.append(point)
+            status = "LSV: \(lsvPoints.count)/\(lsvTotal)"
+
+        case .lsvEnd:
+            saveLsv()
+            status = "LSV complete: \(lsvPoints.count) points"
+
+        case .ampStart(let vHold):
+            ampPoints.removeAll()
+            ampRunning = true
+            status = String(format: "Amp: %.0f mV", vHold)
+
+        case .ampPoint(let index, let point):
+            ampPoints.append(point)
+            ampTotal = index + 1
+            status = "Amp: \(ampPoints.count) pts"
+
+        case .ampEnd:
+            ampRunning = false
+            saveAmp()
+            status = "Amp complete: \(ampPoints.count) points"
+
+        case .clStart(let numPoints):
+            clPoints.removeAll()
+            clResult = nil
+            clTotal = numPoints
+            status = "Chlorine: \(numPoints) pts"
+
+        case .clPoint(_, let point):
+            clPoints.append(point)
+            status = "Chlorine: \(clPoints.count)/\(clTotal)"
+
+        case .clResult(let r):
+            clResult = r
+            status = String(format: "Chlorine: free=%.3f uA, total=%.3f uA", r.iFreeUa, r.iTotalUa)
+
+        case .clEnd:
+            saveCl()
+            status = "Chlorine complete: \(clPoints.count) points"
+
+        case .phResult(let r):
+            if collectingRefs {
+                phRef = r
+            } else {
+                savePh(r)
+                status = String(format: "pH: %.2f (OCP=%.1f mV, T=%.1fC)", r.ph, r.vOcpMv, r.tempC)
+                phResult = r
+            }
+
+        case .temperature(let t):
+            tempC = t
+
+        case .refFrame(let mode, let rtiaIdx):
+            refMode = mode
+            refRtia = rtiaIdx
+            let modeName: String
+            switch mode {
+            case 0: modeName = "EIS"
+            case 1: modeName = "LSV"
+            case 2: modeName = "Amp"
+            case 3: modeName = "Cl"
+            case 4: modeName = "pH"
+            default: modeName = "?"
+            }
+            if mode == 0 {
+                status = "Ref: \(modeName) RTIA \(rtiaIdx + 1)/8"
+            } else {
+                status = "Ref: \(modeName) range search"
+            }
+
+        case .refLpRange:
+            break
+
+        case .refsDone:
+            collectingRefs = false
+            hasDeviceRefs = true
+            refMode = nil
+            refRtia = nil
+            let idx = Int(rtia.rawValue)
+            if idx < 8, let pts = eisRefs[idx] {
+                eisRef = pts
+            }
+            status = "Reference collection complete"
+
+        case .refStatus(let hasRefs):
+            hasDeviceRefs = hasRefs
+            if !hasRefs {
+                status = "No device refs"
+            }
+        }
+    }
+
     // MARK: - Actions
 
     func applyEISSettings() {
         let fs = Float(freqStart) ?? 1000
         let fe = Float(freqStop) ?? 200000
         let p = UInt16(ppd) ?? 10
-        status = "Applying: \(fs)-\(fe) Hz, \(p) PPD"
+        send(buildSysexSetSweep(freqStart: fs, freqStop: fe, ppd: p))
+        send(buildSysexSetRtia(rtia))
+        send(buildSysexSetRcal(rcal))
+        send(buildSysexSetElectrode(electrode))
+        send(buildSysexGetConfig())
     }
 
     func startSweep() {
         eisPoints.removeAll()
-        status = "Starting sweep..."
+        send(buildSysexGetTemp())
+        send(buildSysexStartSweep())
     }
 
     func startLSV() {
         lsvPoints.removeAll()
         let vs = Float(lsvStartV) ?? 0
         let ve = Float(lsvStopV) ?? 500
-        status = "Starting LSV: \(vs)-\(ve) mV"
+        let sr = Float(lsvScanRate) ?? 50
+        send(buildSysexGetTemp())
+        send(buildSysexStartLsv(vStart: vs, vStop: ve, scanRate: sr, lpRtia: lsvRtia))
     }
 
     func startAmp() {
         ampPoints.removeAll()
         ampRunning = true
-        status = "Starting amperometry..."
+        let vh = Float(ampVHold) ?? 200
+        let iv = Float(ampInterval) ?? 100
+        let dur = Float(ampDuration) ?? 60
+        send(buildSysexGetTemp())
+        send(buildSysexStartAmp(vHold: vh, intervalMs: iv, durationS: dur, lpRtia: ampRtia))
     }
 
     func stopAmp() {
-        ampRunning = false
+        send(buildSysexStopAmp())
-        status = "Stopping amperometry..."
     }
 
     func startChlorine() {
         clPoints.removeAll()
         clResult = nil
-        status = "Starting chlorine measurement..."
+        let vCond = Float(clCondV) ?? 800
+        let tCond = Float(clCondT) ?? 2000
+        let vFree = Float(clFreeV) ?? 100
+        let vTotal = Float(clTotalV) ?? -200
+        let tDep = Float(clDepT) ?? 5000
+        let tMeas = Float(clMeasT) ?? 5000
+        send(buildSysexGetTemp())
+        send(buildSysexStartCl(
+            vCond: vCond, tCondMs: tCond, vFree: vFree, vTotal: vTotal,
+            tDepMs: tDep, tMeasMs: tMeas, lpRtia: clRtia
+        ))
     }
 
     func startPh() {
         phResult = nil
-        status = "Starting pH measurement..."
+        let stab = Float(phStabilize) ?? 30
+        send(buildSysexGetTemp())
+        send(buildSysexStartPh(stabilizeS: stab))
     }
 
     func setReference() {
@@ -155,29 +361,37 @@ final class AppState {
         case .amp: ampRef = nil; status = "Amp reference cleared"
         case .chlorine: clRef = nil; status = "Chlorine reference cleared"
         case .ph: phRef = nil; status = "pH reference cleared"
-        case .sessions: break
+        case .sessions, .connection: break
         }
     }
 
     func collectRefs() {
         collectingRefs = true
+        eisRefs.removeAll()
         status = "Starting reference collection..."
+        send(buildSysexStartRefs())
+    }
+
+    func getRefs() {
+        collectingRefs = true
+        eisRefs.removeAll()
+        send(buildSysexGetRefs())
     }
 
     func clearRefs() {
         collectingRefs = false
         hasDeviceRefs = false
+        eisRefs.removeAll()
         eisRef = nil
-        lsvRef = nil
-        ampRef = nil
-        clRef = nil
         phRef = nil
+        send(buildSysexClearRefs())
         status = "Refs cleared"
     }
 
     func startClean() {
         let v = Float(cleanV) ?? 1200
         let d = Float(cleanDur) ?? 30
+        send(buildSysexStartClean(vMv: v, durationS: d))
         status = String(format: "Cleaning: %.0f mV for %.0fs", v, d)
     }
 
@@ -188,7 +402,7 @@ final class AppState {
         case .amp: ampRef != nil
         case .chlorine: clRef != nil
         case .ph: phRef != nil
-        case .sessions: false
+        case .sessions, .connection: false
         }
     }
 
@@ -199,10 +413,97 @@ final class AppState {
         case .amp: !ampPoints.isEmpty
         case .chlorine: clResult != nil
         case .ph: phResult != nil
-        case .sessions: false
+        case .sessions, .connection: false
         }
     }
 
+    // MARK: - Auto-save
+
+    private func saveEis() {
+        guard let sid = currentSessionId else { return }
+        let params: [String: String] = [
+            "freq_start": freqStart,
+            "freq_stop": freqStop,
+            "ppd": ppd,
+            "rtia": rtia.label,
+            "rcal": rcal.label,
+            "electrode": electrode.label,
+        ]
+        guard let configData = try? JSONEncoder().encode(params) else { return }
+        guard var meas = try? Storage.shared.addMeasurement(sessionId: sid, type: .eis) else { return }
+        meas.config = configData
+        guard let mid = meas.id else { return }
+        let indexed = eisPoints.enumerated().map { (index: $0.offset, value: $0.element) }
+        try? Storage.shared.addDataPoints(measurementId: mid, points: indexed)
+    }
+
+    private func saveLsv() {
+        guard let sid = currentSessionId else { return }
+        let params: [String: String] = [
+            "v_start": lsvStartV,
+            "v_stop": lsvStopV,
+            "scan_rate": lsvScanRate,
+            "rtia": lsvRtia.label,
+        ]
+        guard let configData = try? JSONEncoder().encode(params) else { return }
+        guard var meas = try? Storage.shared.addMeasurement(sessionId: sid, type: .lsv) else { return }
+        meas.config = configData
+        guard let mid = meas.id else { return }
+        let indexed = lsvPoints.enumerated().map { (index: $0.offset, value: $0.element) }
+        try? Storage.shared.addDataPoints(measurementId: mid, points: indexed)
+    }
+
+    private func saveAmp() {
+        guard let sid = currentSessionId else { return }
+        let params: [String: String] = [
+            "v_hold": ampVHold,
+            "interval_ms": ampInterval,
+            "duration_s": ampDuration,
+            "rtia": ampRtia.label,
+        ]
+        guard let configData = try? JSONEncoder().encode(params) else { return }
+        guard var meas = try? Storage.shared.addMeasurement(sessionId: sid, type: .amp) else { return }
+        meas.config = configData
+        guard let mid = meas.id else { return }
+        let indexed = ampPoints.enumerated().map { (index: $0.offset, value: $0.element) }
+        try? Storage.shared.addDataPoints(measurementId: mid, points: indexed)
+    }
+
+    private func saveCl() {
+        guard let sid = currentSessionId else { return }
+        let params: [String: String] = [
+            "cond_v": clCondV,
+            "cond_t": clCondT,
+            "free_v": clFreeV,
+            "total_v": clTotalV,
+            "dep_t": clDepT,
+            "meas_t": clMeasT,
+            "rtia": clRtia.label,
+        ]
+        guard let configData = try? JSONEncoder().encode(params) else { return }
+        guard var meas = try? Storage.shared.addMeasurement(sessionId: sid, type: .chlorine) else { return }
+        meas.config = configData
+        guard let mid = meas.id else { return }
+        let indexed = clPoints.enumerated().map { (index: $0.offset, value: $0.element) }
+        try? Storage.shared.addDataPoints(measurementId: mid, points: indexed)
+        if let r = clResult {
+            try? Storage.shared.setMeasurementResult(mid, result: r)
+        }
+    }
+
+    private func savePh(_ result: PhResult) {
+        guard let sid = currentSessionId else { return }
+        let params: [String: String] = [
+            "stabilize_s": phStabilize,
+        ]
+        guard let configData = try? JSONEncoder().encode(params) else { return }
+        guard var meas = try? Storage.shared.addMeasurement(sessionId: sid, type: .ph) else { return }
+        meas.config = configData
+        guard let mid = meas.id else { return }
+        try? Storage.shared.addDataPoint(measurementId: mid, index: 0, point: result)
+        try? Storage.shared.setMeasurementResult(mid, result: result)
+    }
+
     // MARK: - Measurement loading
 
     func loadMeasurement(_ measurement: Measurement) {

cue-ios/CueIOS/BLE/BLEManager.swift

@@ -8,8 +8,8 @@ import Foundation
 @Observable
 final class BLEManager: NSObject {
 
-    static let midiServiceUUID = CBUUID(string: "03B80E5A-EDE8-4B33-A751-6CE34EC4C700")
+    nonisolated(unsafe) static let midiServiceUUID = CBUUID(string: "03B80E5A-EDE8-4B33-A751-6CE34EC4C700")
-    static let midiCharUUID    = CBUUID(string: "7772E5DB-3868-4112-A1A9-F2669D106BF3")
+    nonisolated(unsafe) static let midiCharUUID    = CBUUID(string: "7772E5DB-3868-4112-A1A9-F2669D106BF3")
 
     enum ConnectionState: String {
         case disconnected = "Disconnected"
@@ -18,11 +18,20 @@ final class BLEManager: NSObject {
         case connected    = "Connected"
     }
 
+    struct DiscoveredDevice: Identifiable {
+        let id: UUID
+        let peripheral: CBPeripheral
+        let name: String
+        let rssi: Int
+        var serviceUUIDs: [CBUUID]
+    }
+
     var state: ConnectionState = .disconnected
     var lastMessage: EisMessage?
+    var discoveredDevices: [DiscoveredDevice] = []
 
     private var centralManager: CBCentralManager!
-    private var peripheral: CBPeripheral?
+    private(set) var peripheral: CBPeripheral?
     private var midiCharacteristic: CBCharacteristic?
     private var onMessage: ((EisMessage) -> Void)?
 
@@ -36,14 +45,32 @@ final class BLEManager: NSObject {
     }
 
     func startScanning() {
-        guard centralManager.state == .poweredOn else { return }
+        guard centralManager.state == .poweredOn else {
+            print("[BLE] can't scan, state: \(centralManager.state.rawValue)")
+            return
+        }
+        print("[BLE] starting scan (no filter)")
         state = .scanning
+        discoveredDevices.removeAll()
         centralManager.scanForPeripherals(
-            withServices: [Self.midiServiceUUID],
+            withServices: nil,
-            options: nil
+            options: [CBCentralManagerScanOptionAllowDuplicatesKey: false]
         )
     }
 
+    func stopScanning() {
+        centralManager.stopScan()
+        if state == .scanning { state = .disconnected }
+    }
+
+    func connectTo(_ device: DiscoveredDevice) {
+        centralManager.stopScan()
+        peripheral = device.peripheral
+        state = .connecting
+        print("[BLE] connecting to \(device.name)")
+        centralManager.connect(device.peripheral, options: nil)
+    }
+
     func disconnect() {
         if let p = peripheral {
             centralManager.cancelPeripheralConnection(p)
@@ -105,6 +132,7 @@ final class BLEManager: NSObject {
 extension BLEManager: CBCentralManagerDelegate {
 
     func centralManagerDidUpdateState(_ central: CBCentralManager) {
+        print("[BLE] centralManager state: \(central.state.rawValue)")
         if central.state == .poweredOn {
             startScanning()
         }
@@ -116,11 +144,21 @@ extension BLEManager: CBCentralManagerDelegate {
         advertisementData: [String: Any],
         rssi RSSI: NSNumber
     ) {
-        guard peripheral.name == "EIS4" else { return }
+        let name = peripheral.name ?? advertisementData[CBAdvertisementDataLocalNameKey] as? String ?? "Unknown"
-        central.stopScan()
+        let svcUUIDs = advertisementData[CBAdvertisementDataServiceUUIDsKey] as? [CBUUID] ?? []
-        self.peripheral = peripheral
+
-        state = .connecting
+        print("[BLE] found: \(name) rssi:\(RSSI) services:\(svcUUIDs)")
-        central.connect(peripheral, options: nil)
+
+        if discoveredDevices.contains(where: { $0.id == peripheral.identifier }) { return }
+
+        let device = DiscoveredDevice(
+            id: peripheral.identifier,
+            peripheral: peripheral,
+            name: name,
+            rssi: RSSI.intValue,
+            serviceUUIDs: svcUUIDs
+        )
+        discoveredDevices.append(device)
     }
 
     func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {

cue-ios/CueIOS/CueIOSApp.swift

@@ -2,11 +2,14 @@ import SwiftUI
 
 @main
 struct CueIOSApp: App {
-    @State private var ble = BLEManager()
+    @State private var state = AppState()
 
     var body: some Scene {
         WindowGroup {
-            ContentView()
+            ContentView(state: state)
+                .onReceive(Timer.publish(every: 0.25, on: .main, in: .common).autoconnect()) { _ in
+                    state.updateConnectionState()
+                }
         }
     }
 }

cue-ios/CueIOS/Info.plist

@@ -2,6 +2,18 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleName</key>
+	<string>$(PRODUCT_NAME)</string>
+	<key>CFBundleVersion</key>
+	<string>1</string>
+	<key>CFBundleShortVersionString</key>
+	<string>1.0</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
 	<key>NSBluetoothAlwaysUsageDescription</key>
 	<string>EIS4 uses Bluetooth to communicate with the impedance analyzer</string>
 	<key>UIBackgroundModes</key>

cue-ios/CueIOS/Models/Storage.swift

@@ -43,7 +43,7 @@ struct DataPoint: Codable, FetchableRecord, MutablePersistableRecord {
 
 // MARK: - Database manager
 
-final class Storage {
+final class Storage: @unchecked Sendable {
     static let shared = Storage()
 
     private let dbQueue: DatabaseQueue

cue-ios/CueIOS/Views/ConnectionView.swift

@@ -0,0 +1,87 @@
+import SwiftUI
+
+struct ConnectionView: View {
+    var state: AppState
+
+    var body: some View {
+        VStack(spacing: 0) {
+            header
+            Divider()
+            deviceList
+        }
+        .navigationTitle("Connection")
+    }
+
+    private var header: some View {
+        HStack {
+            Circle()
+                .fill(statusColor)
+                .frame(width: 10, height: 10)
+            Text(state.ble.state.rawValue)
+                .font(.headline)
+            Spacer()
+            if state.ble.state == .connected {
+                Button("Disconnect") { state.ble.disconnect() }
+                    .buttonStyle(.bordered)
+                    .tint(.red)
+            } else if state.ble.state == .scanning {
+                Button("Stop") { state.ble.stopScanning() }
+                    .buttonStyle(.bordered)
+            } else {
+                Button("Scan") { state.ble.startScanning() }
+                    .buttonStyle(.borderedProminent)
+            }
+        }
+        .padding()
+    }
+
+    private var statusColor: Color {
+        switch state.ble.state {
+        case .connected: .green
+        case .scanning: .orange
+        case .connecting: .yellow
+        case .disconnected: .red
+        }
+    }
+
+    private var deviceList: some View {
+        List {
+            if state.ble.discoveredDevices.isEmpty && state.ble.state == .scanning {
+                HStack {
+                    ProgressView()
+                    Text("Scanning for devices...")
+                        .foregroundStyle(.secondary)
+                }
+            }
+
+            ForEach(state.ble.discoveredDevices) { device in
+                Button {
+                    state.ble.connectTo(device)
+                } label: {
+                    HStack {
+                        VStack(alignment: .leading, spacing: 2) {
+                            Text(device.name)
+                                .font(.body.weight(.medium))
+                            if !device.serviceUUIDs.isEmpty {
+                                Text(device.serviceUUIDs.map(\.uuidString).joined(separator: ", "))
+                                    .font(.caption2)
+                                    .foregroundStyle(.secondary)
+                                    .lineLimit(1)
+                            }
+                        }
+                        Spacer()
+                        Text("\(device.rssi) dBm")
+                            .font(.caption)
+                            .foregroundStyle(.secondary)
+                        if device.name == "EIS4" {
+                            Image(systemName: "star.fill")
+                                .foregroundStyle(.yellow)
+                                .font(.caption)
+                        }
+                    }
+                }
+                .disabled(state.ble.state == .connecting)
+            }
+        }
+    }
+}

cue-ios/CueIOS/Views/ContentView.swift

@@ -1,7 +1,7 @@
 import SwiftUI
 
 struct ContentView: View {
-    @State private var state = AppState()
+    @Bindable var state: AppState
     @Environment(\.horizontalSizeClass) private var sizeClass
 
     var body: some View {
@@ -40,6 +40,7 @@ struct ContentView: View {
             }
             Section("Data") {
                 sidebarButton(.sessions, "Sessions", "folder")
+                sidebarButton(.connection, "Connection", "antenna.radiowaves.left.and.right")
             }
             Section {
                 cleanControls
@@ -126,6 +127,10 @@ struct ContentView: View {
             SessionView(state: state)
                 .tabItem { Label("Sessions", systemImage: "folder") }
                 .tag(Tab.sessions)
+
+            ConnectionView(state: state)
+                .tabItem { Label("Connection", systemImage: "antenna.radiowaves.left.and.right") }
+                .tag(Tab.connection)
         }
     }
 
@@ -140,6 +145,7 @@ struct ContentView: View {
         case .chlorine: ChlorineView(state: state)
         case .ph: PhView(state: state)
         case .sessions: SessionView(state: state)
+        case .connection: ConnectionView(state: state)
         }
     }
 }

main/ble.c

@@ -30,7 +30,7 @@ static const ble_uuid128_t midi_chr_uuid = BLE_UUID128_INIT(
     0xf3, 0x6b, 0x10, 0x9d, 0x66, 0xf2, 0xa9, 0xa1,
     0x12, 0x41, 0x68, 0x38, 0xdb, 0xe5, 0x72, 0x77);
 
-#define MAX_CONNECTIONS 2
+#define MAX_CONNECTIONS 4
 
 static EventGroupHandle_t ble_events;
 static QueueHandle_t cmd_queue;
@@ -523,8 +523,13 @@ static int gap_event_cb(struct ble_gap_event *event, void *arg)
     return 0;
 }
 
-static void start_adv(void)
+static void adv_task(void *param)
 {
+    (void)param;
+    vTaskDelay(pdMS_TO_TICKS(200));
+
+    ble_gap_adv_stop();
+
     struct ble_hs_adv_fields fields = {0};
     fields.flags = BLE_HS_ADV_F_DISC_GEN | BLE_HS_ADV_F_BREDR_UNSUP;
     fields.name = (uint8_t *)DEVICE_NAME;
@@ -539,19 +544,38 @@ static void start_adv(void)
     fields.uuids16 = adv_uuids;
     fields.num_uuids16 = 2;
     fields.uuids16_is_complete = 0;
-    ble_gap_adv_set_fields(&fields);
+
+    int rc = ble_gap_adv_set_fields(&fields);
+    if (rc) { printf("BLE: set_fields failed: %d\n", rc); goto done; }
 
     struct ble_hs_adv_fields rsp = {0};
     rsp.uuids128 = (ble_uuid128_t *)&midi_svc_uuid;
     rsp.num_uuids128 = 1;
     rsp.uuids128_is_complete = 1;
-    ble_gap_adv_rsp_set_fields(&rsp);
+
+    rc = ble_gap_adv_rsp_set_fields(&rsp);
+    if (rc) { printf("BLE: set_rsp failed: %d\n", rc); goto done; }
 
     struct ble_gap_adv_params params = {0};
     params.conn_mode = BLE_GAP_CONN_MODE_UND;
     params.disc_mode = BLE_GAP_DISC_MODE_GEN;
-    ble_gap_adv_start(BLE_OWN_ADDR_PUBLIC, NULL, BLE_HS_FOREVER,
+    params.itvl_min = BLE_GAP_ADV_FAST_INTERVAL1_MIN;
-                      &params, gap_event_cb, NULL);
+    params.itvl_max = BLE_GAP_ADV_FAST_INTERVAL1_MAX;
+
+    rc = ble_gap_adv_start(BLE_OWN_ADDR_PUBLIC, NULL, BLE_HS_FOREVER,
+                           &params, gap_event_cb, NULL);
+    if (rc)
+        printf("BLE: adv_start failed: %d\n", rc);
+    else
+        printf("BLE: advertising (%d connected)\n", conn_count);
+
+done:
+    vTaskDelete(NULL);
+}
+
+static void start_adv(void)
+{
+    xTaskCreate(adv_task, "adv", 2048, NULL, 5, NULL);
 }
 
 static void on_sync(void)

sdkconfig.defaults

@@ -1,7 +1,7 @@
 CONFIG_IDF_TARGET="esp32s3"
 CONFIG_BT_ENABLED=y
 CONFIG_BT_NIMBLE_ENABLED=y
-CONFIG_BT_NIMBLE_MAX_CONNECTIONS=2
+CONFIG_BT_NIMBLE_MAX_CONNECTIONS=4
 CONFIG_BT_NIMBLE_ROLE_PERIPHERAL=y
 CONFIG_BT_NIMBLE_ROLE_CENTRAL=y
 CONFIG_BT_NIMBLE_ROLE_OBSERVER=n